基于CPLD的超低频/超大脉宽信号源的电路设计  

A long-duration pulse generator

作　　者：李素琴[1,2] 苏弘[1] 李勇[1,2] 千奕[1,2] 彭宇[1,2] 董成富[1] 李小刚[1] 马晓莉[1] 

机构地区：[1]中国科学院近代物理研究所 [2]中国科学院研究生院北京100049

出　　处：《核技术》2006年第5期396-400,共5页Nuclear Techniques

摘　　要：介绍了一种基于复杂可编程逻辑器件(Complexprogrammablelogicdevice,CPLD)设计的超低频/超大脉宽脉冲信号产生器。它的主要功能是产生低频、超低频/超大脉宽脉冲信号,其最大周期Tmax>1000s,最小周期Tmin=1ms。其脉宽可在1/1000T—999/1000T范围内以T/1000步进调节。输出脉冲f/T的精确度<0.02‰,输出脉冲f/T的稳定性<±0.01‰。输出脉冲分连续输出和单次手动触发输出。该电路可以输出TTL/TTL和NIM/NIM信号。NIM快信号的上升时间tr<4ns,下降时间tf<4ns。我们用复杂可编程逻辑器件CPLD来构建主要部分电路,和常规逻辑器件相比其突出特点是:元件少、成本低、功耗低。A CPLD-based long-duration pulse generator, which can generate singular or continuous pulse with ultra-low repetition rate/long cycle, is introduced in this paper. The cycle （T） of output pulses generated by this generator can be selected in a range from Tmin=1 ms to Tmax〉1000 s. Also, the width of the output pulse can be adjusted from 1/1000 cycle to 999/1000 cycle stepped by 1/1000 cycle. Accuracy of the repetition rate（f） of output pulses is 〈0.02‰, and the long-term instability of is within ±0.01%o. There are two modes selectable for output pulses, singular pulse output and repetitive pulse output, which can be set by a two-position switch. When the singular pulse output mode is selected, only one pulse can be generated each time by pressing an external control push-button. This pulser can provide both TTL/TTL output signals and NIM/NIM output signals. The risetime of the NIM output signal is tr〈4ns and the falltime is tf〈4ns. We use CPLD to construct the main circuits. Compared with the circuits constructed by TTL devices, the new pulse generator has features such as less components, lower cost and lower dissipation.

关 键 词：复杂可编程逻辑器件 超低频 超大脉宽 脉冲信号 产生器 

分 类 号：TN78[电子电信—电路与系统]